1. Field of the Invention
This invention relates to an improved thermally actuatable electrical switch construction and to a method of making the same.
2. Prior Art Statement
It is known to provide a thermally actuatable electrical switch construction having a resilient contact member normally biased into electrical contact with a stationary contact member while a temperature sensitive member of the construction is in a solid condition and normally springing out of contact with the stationary contact member by the natural bias of the resilient contact member when the temperature sensitive member is rendered non-solid by sensing a temperature above a predetermined temperature.
For example, see the following item:
(1) U.S. Pat. No. 3,827,014--Wehl PA1 (2) U.S. Pat. No. 4,167,724--McCaughna PA1 (3) German Pat. No. 2,837,827--Hara PA1 (4) U.S. Pat. No. 4,184,139--Hara PA1 (5) Ser. No. 085,216, filed Oct. 16, 1979--Candor. PA1 (5) U.S. Pat. No. 3,930,215--Senor PA1 (6) U.S. Pat. No. 3,944,960--Audette et al PA1 (7) U.S. Pat. No. 4,109,229--Plasko PA1 (8) German Pat. No. 2,911,950--Olson et al.
It is also known to provide such a thermally actuatable electrical switch construction wherein the resilient contact member can comprise a hollow body carried by the insulated terminal and be radially expanded outwardly into electrical contact with a conductive casing side wall by the solid temperature sensing member and spring radially inwardly out of contact with the casing side wall when the temperature sensitive member is rendered non-solid.
For example, see the following three items:
It is also known to applicant to provide a guide means that is carried by the thermally actuatable electrical switch construction and is operatively associated with the resilient contact member to provide a guide for the resilient contact member that will substantially insure that the resilient contact member will move and be maintained out of contact with a stationary contact member of the construction after the temperature sensitive member has been rendered non-solid, the guide means comprising a cup-shaped member which will telescope over the resilient contact member under the force of a compression spring when the temperature sensitive member has been rendered non-solid.
For example, see the following item:
The compression spring of item (4) above does not engage the resilient contact member and, in effect, pushes the resilient contact member out of contact with the stationary contact member when the temperature sensitive member has been rendered non-solid.
There are other prior known thermally actuatable electrical switch constructions wherein a compression spring, in effect, pushes the resilient contact member out of contact with the stationary contact member in a manner to actually deform the resilient contact member away from the stationary contact member.
For example, see the following four items: